| 摘要 |
PURPOSE:To reduce the running cost and enable to automatically take anti- freezing measures by a method wherein the start and stop of a burner is controlled by means of a flow switch and a thermostat during the operation for hot water supply, while the burner is controlled only by means of the thermostat during the operation for anti-freezing. CONSTITUTION:During the operation for hot water supply, a change-over switch 12 is connected to a ''hot water supplying operation'' side. When a flow switch 10 senses the water flow, the switch 10 makes itself closed in order to operate a burner 3. In this case, the operation of the burner 3 is controlled by a thermostate arranged in a water circuit. During the operation for anti-freezing, when the change-over switch 12 is connected to a ''anti-freezing'' side, the operation of the burner3 is controlled only by the thermostat 13, even if no water flow is generated, because the use of the flow switch 10 is eliminated. |
